I'm afraid that your solutions to 1, 3, 4, and 5 must be disqualified.

Hole 1 specifies returning the fifth word; your solution returns some extra whitespace. Additionally, there may be no whitespace after the fifth word, or after any of the words:
first-second!third+fourth*fifth.

For Hole 3, the entire string must consist of the repeated substring. This was demonstrated in the examples, where 'ababab' results in 'ab' but 'ababaaa' results in ''.

Hole 4 asks for a list of characters, rather than a string. Looks like that one tripped up a lot of people. :)

Hole 5 features a common gotcha; a correct solution must handle the case where all the values in the list are negative. Another one that a lot of people don't catch. :)

We tried to make things a little easier at the actual tournament by providing a test scaffold for each hole, which the participants could use to test their code on sample input. Solving these holes is much harder without that.

Ada Lovelace for the palindrome
Albert Einstein for having smelly feet
Alfred Nobel for his contribution to battlefield science
Burkhard Heim for providing the missing link between science and mysticism
Claude Shannnon for riding a unicycle at night at MIT
Donald Knuth for being such a great organist
Edward Teller for being the template for Dr. Strangelove
Edwin Hubble for pretending to be a pipe-smoking English gentleman
Erwin Schrödinger for cruelty to cats
Hedy Lamarr for weaponizing pianos
Hugh Everett for immortality, especially for cats
Isaac Newton for his occult studies
Kikunae Ikeda for discovering the secrets of soy sauce
Larry Wall for his website
Louis Camille Maillard for discovering why steaks taste good
Marie Curie for the shiny stuff
Nikola Tesla for the cool cars
Paul Dirac for speaking one word per hour when socializing
Richard Feynman for his bongo skills
Robert Oppenheimer for his in-depth knowledge of the Bhagavad Gita
Rusi P Taleyarkhan for Cold Fusion
Sigmund Freud for his Ménage ā trois
Theodor W Adorno for his contribution to the reception of jazz
Wilhelm Röntgen for the foundations of body scanners
Yulii Borisovich Khariton for the Tsar Bomba
Other (please explain why)